Illustrative examples of threaded fasteners used to hold together two work pieces are nuts and bolts used to hold together a flange connection. Installing and removing nuts and bolts from flange connections and the like is often difficult, particularly if the flange connections have been exposed to harsh weather or corrosive conditions, and particularly if the flange connections are several inches in diameter. It is common to employ two persons for tightening and/or loosening the flange connection. One person usually holds a backup wrench to retain the nut or bolt head on one side of the connection to prevent it from rotating, while another person usually uses a second wrench to apply torque to the nut or bolt head on the opposite side of the connection. Each time torque is applied to a bolt/nut combination, the backup wrench is typically jammed against an adjacent bolt/nut combination or some other stationary object. When the torquing process is complete, the backup wrench typically has to be knocked loose using a large hammer. This procedure is not only unsafe, but it is also time consuming, labor intensive, and costly. The present invention provides a tool and method that makes this procedure simpler, safer, faster, and more cost-effective.
There are several patents which disclose various devices for locking a nut or bolt to prevent relative rotation between the nut and bolt. Madsen, U.S. Pat. No. 3,351,116, discloses a pair of inter-engageable plate members having central apertures into which the polygonally-shaped heads of bolts are adapted to be inserted, and whereby the projecting edges or corners of the bolt heads will contact adjoining surface portions of the respective aperture in the plate members in which they are located such that during tightening and torquing of nuts which are in screw-fitted engagement with the bolt shanks, this preventing of rotation of the bolts will facilitate the tightening process by a worker.
Sjostrom, U.S. Pat. No. 4,104,936, discloses a holding device that facilitates the tightening of a screw joint projecting from both sides of a pair of plates. The device includes an arm which, at which one end, features an organ for a torque transmitting engagement with a part belonging to the screw joint, and at the other end, features a lateral stop which includes a cam body or eccentric assembly designed to abut against an edge of at least one plate or flange.
Michaud, U.S. Pat. No. 4,274,310, discloses a torque multiplication device for use in tightening or loosening a nut, lug, bolt head and the like, which employs a planetary transmission of sun, planet, and orbit gear means to multiply the applied torque input to produce an output torque to facilitate and simplify such tightening and loosening.
Steele et al, U.S. Pat. No. 4,329,097, discloses a pair of nut locking cups that engage the external surfaces of a pair of nuts and have an outside radius equal to one-half of the distances between adjacent studs with a locking bar welded to the cups and between adjacent studs.
Hiraiwa, U.S. Pat. No. 4,475,857, discloses a detent apparatus in which a plate has polygonally-sided recesses or cutouts formed at oppositely located edges thereof, each engageable by a close-fitting hexagonal member so as to inhibit relative rotation between the hexagonal members responsive to the application of rotational moments thereto.
Gallagher et al, U.S. Pat. No. 4,735,533, and Linderman et al, Design U.S. Des. Pat. No. 305,927, disclose a locking assembly for locking a nut to a valve body which utilizes a lock plate with a peripheral depending skirt having an opening which surrounds the nut-like portion of a valve bonnet and has a slot spaced from the opening which receives a set screw and a nut to secure the lock plate to the valve body.
Martin et al, U.S. Pat. No. 5,415,509, discloses an adjustable locking plate with a rectangular central aperture defined by upwardly bent straps and opposed arcuate end edges and opposed arcuate slots which receive bolts.
Puskas, U.S. Pat. No. 5,429,465, discloses a retainer structure for preventing relative rotation between a plurality of spaced apart nut-like fasteners utilizing a plurality of apertured plates each having a central polygonal aperture which is placed on a nut-like fastener and having opposed ends that are cut out to surround one-half of the adjacent nut-like fastener.
Coffey et al, U.S. Pat. No. 5,954,466, discloses an anti-rotation clip for preventing rotation of a nut-like member of a flanged connection to facilitate tightening or loosening of the nut-like member and eliminate the need to use two wrenches for tightening or loosening a nut or bolt.
DeLand, U.S. Pat. No. 6,427,558, discloses a reaction cam system, wherein the reaction cam applies a reaction force to a backup wrench coupled between a head of a fastener and an adjacent component. The reaction cam is positioned against the backup wrench and has an inner sleeve removably coupled to a head of the fastener.